javadoc fixes

Change-Id: I3b4fc2d99f42b2413a535fb411b9c19bdd186ad8
diff --git a/utils/misc/src/main/java/org/onlab/util/HexString.java b/utils/misc/src/main/java/org/onlab/util/HexString.java
index 4e46a25..3e9ae03 100644
--- a/utils/misc/src/main/java/org/onlab/util/HexString.java
+++ b/utils/misc/src/main/java/org/onlab/util/HexString.java
@@ -24,7 +24,7 @@
     /**
      * Convert a string of bytes to a ':' separated hex string.
      *
-     * @param bytes
+     * @param bytes string of bytes to convert
      * @return "0f:ca:fe:de:ad:be:ef"
      */
     public static String toHexString(final byte[] bytes) {